Grades aren't the only factor.

• Position: In college admissions

A common dilemma for college-bound high school students is whether they should take the easier math course and get an A or calculus and risk getting a B or even a C on their transcripts, If they seek admission to highly selective schools, admissions officers say, they should go ahead and take the more challenging course.

"As we travel around the country, we find there's a lot of confusion among students and parents about the value that selective schools place on rigorous academic courses," notes James Montoya, dean of undergraduate admissions at Stanford University. "We do not depend heavily on grade point averages to give us a sense of student accomplishment. As we view each file individually, we also take into consideration many other factors, including the depth and breadth of a student's academic preparation."

The main problem with relying largely on grade point averages (GPAs) is that there are more than 25,000 high schools in the U.S., and they vary wildly in how they present information about their students. Some provide detailed class profiles showing exactly where the applicant stands in comparison with his or her peers, while others don't rank their students at all.

Grading policies also can be radically different, depending on the school's philosophy. Some parcel out A's only for truly exceptional work, while others automatically inflate the grade point averages of all their honors students, so that those getting B's in tough classes actually end up with A's on their...